Team Fortress 2 is a very well designed, this is to be hoped for considering it took 9 years to develop. The game appropriately uses affordances when respawning, marking capture points, labelling one way doors and marking the boundaries of outdoor maps. Upon spawning, the player always faces the enemy base, so that they are always properly oriented. Capture points stand out from their surroundings, always being circular, coloured when captured and central to arena spaces. One way doors are marked by a large red octagon with a hand in the centre, representing multiple stop signs at once. And finally TF2 uses affordances to mark the edges of the map by having simple low fences with boring landscapes beyond that signify to the player that it is the boundary.
TF2 cleverly uses constraints to encourage certain patterns of play. It limits the fire rate on certain characters to encourage the play style they are designed for, uses one way doors to limit flow of attack and defence, and has tight paths with many corners to encourage players to fight in arenas around capture points.
With multiple characters in TF2, there is obviously many interesting design choices to make them individual. The Medic’s invulnerability allows for quick charges to take tight, contested spots. However, the graphical component of this helps signify to opposing players of the invulnerability and gives them confidence that it will not last long. Allowing the spy to go invisible to sneak past the front lines then to disguise as another character gives them the ability to use their backstab ability to instantly kill an enemy. However making the invisibility limited by a timer causes haste in the player’s actions, making room for mistakes and panic. Finally, by giving the soldier the ability to rocket jump, he is able to gain a height advantage on the battlefield. However, it does cost the soldier a significant amount of health, requiring him to rely on the medic for support.
TF2 has also made other interesting design choices to ease the flow of combat and to not overwhelm new players. They designers have chosen to add a highlight to the edges of every player model so that they do not blend into the background when moving around the maps. They also made sure every character had a very distinct silhouette so that players could easily identify what they were facing.